Many electronic devices include one or more rechargeable batteries that require external power to recharge from time to time. Often, these devices may be charged using the same or similar connection type, for example via universal serial bus (“USB”). However, despite having common connection types, multiple devices often require separate power supplies with different power outputs. These separate power supplies are burdensome to use, store, and transport from place to place. As a result, the benefits of device portability are substantially limited.
Furthermore, charging cords may be unsafe to use in certain circumstances. For example, a driver of a vehicle may become distracted attempting to plug an electronic device into a vehicle charger. In another example, a charging cord may present a tripping hazard if left unattended.
To account for these and other shortcomings of portable electronic devices, some devices include an inductive recharging system. The user may simply place the device on an inductive charging surface in order for the battery to be recharged. However, due to extra circuitry within the portable electronic device required to support the inductive charging system, battery life of the device may be undesirably reduced. For example, to maintain or reduce the form factor of the device, the battery may be reduced in size or capacity. In another example, the inductive charging system may present a load to the battery when the system is not in use, reducing battery life. Accordingly, although inductively charged devices may be more convenient for the user, they may need to be recharged more often.
Therefore, there may be a present need for a method of delivering useful power to a portable device that does not require a separate power supply and does not itself deplete the battery of the portable electronic device.